transmission/libtransmission/rpc-server.c

723 lines
20 KiB
C

/*
* This file Copyright (C) 2008 Charles Kerr <charles@rebelbase.com>
*
* This file is licensed by the GPL version 2. Works owned by the
* Transmission project are granted a special exemption to clause 2(b)
* so that the bulk of its code can remain under the MIT license.
* This exemption does not extend to derived works not owned by
* the Transmission project.
*
* $Id$
*/
#include <assert.h>
#include <ctype.h> /* isdigit */
#include <errno.h>
#include <stdlib.h> /* strtol */
#include <string.h>
#include <unistd.h> /* unlink */
#include <libevent/event.h>
#include <shttpd/defs.h> /* edit_passwords */
#include <shttpd/shttpd.h>
#include "transmission.h"
#include "bencode.h"
#include "list.h"
#include "platform.h"
#include "rpc.h"
#include "rpc-server.h"
#include "utils.h"
#define MY_NAME "RPC Server"
#define MY_REALM "Transmission RPC Server"
#define ACTIVE_INTERVAL_MSEC 40
#define INACTIVE_INTERVAL_MSEC 200
struct tr_rpc_server
{
int port;
time_t lastRequestTime;
struct shttpd_ctx * ctx;
tr_handle * session;
struct event timer;
int isPasswordEnabled;
char * username;
char * password;
char * acl;
tr_list * connections;
};
#define dbgmsg(fmt...) tr_deepLog(__FILE__, __LINE__, MY_NAME, ##fmt )
static const char*
tr_memmem( const char * s1, size_t l1,
const char * s2, size_t l2 )
{
if (!l2) return s1;
while (l1 >= l2) {
l1--;
if (!memcmp(s1,s2,l2))
return s1;
s1++;
}
return NULL;
}
/**
***
**/
struct ConnBuf
{
char * key;
time_t lastActivity;
struct evbuffer * in;
struct evbuffer * out;
};
static char*
buildKey( struct shttpd_arg * arg )
{
return tr_strdup_printf( "%s %s",
shttpd_get_env( arg, "REMOTE_ADDR" ),
shttpd_get_env( arg, "REQUEST_URI" ) );
}
static struct ConnBuf*
getBuffer( tr_rpc_server * server, struct shttpd_arg * arg )
{
tr_list * l;
char * key = buildKey( arg );
struct ConnBuf * found = NULL;
for( l=server->connections; l && !found; l=l->next )
{
struct ConnBuf * buf = l->data;
if( !strcmp( key, buf->key ) )
found = buf;
}
if( found == NULL )
{
found = tr_new0( struct ConnBuf, 1 );
found->lastActivity = time( NULL );
found->key = tr_strdup( key );
found->in = evbuffer_new( );
found->out = evbuffer_new( );
tr_list_append( &server->connections, found );
}
tr_free( key );
return found;
}
static void
pruneBuf( tr_rpc_server * server, struct ConnBuf * buf )
{
tr_list_remove_data( &server->connections, buf );
evbuffer_free( buf->in );
evbuffer_free( buf->out );
tr_free( buf->key );
tr_free( buf );
}
/**
***
**/
static void
handle_upload( struct shttpd_arg * arg )
{
struct tr_rpc_server * s = arg->user_data;
s->lastRequestTime = time( NULL );
struct ConnBuf * cbuf = getBuffer( s, arg );
/* if we haven't parsed the POST, do that now */
if( !EVBUFFER_LENGTH( cbuf->out ) )
{
/* if we haven't finished reading the POST, read more now */
evbuffer_add( cbuf->in, arg->in.buf, arg->in.len );
arg->in.num_bytes = arg->in.len;
if( arg->flags & SHTTPD_MORE_POST_DATA )
return;
const char * query_string = shttpd_get_env( arg, "QUERY_STRING" );
const char * content_type = shttpd_get_header( arg, "Content-Type" );
const char * delim;
const char * in = (const char *) EVBUFFER_DATA( cbuf->in );
size_t inlen = EVBUFFER_LENGTH( cbuf->in );
char * boundary = tr_strdup_printf( "--%s", strstr( content_type, "boundary=" ) + strlen( "boundary=" ) );
const size_t boundary_len = strlen( boundary );
char buf[64];
int paused = ( query_string != NULL )
&& ( shttpd_get_var( "paused", query_string, strlen( query_string ), buf, sizeof( buf ) ) == 4 )
&& ( !strcmp( buf, "true" ) );
delim = tr_memmem( in, inlen, boundary, boundary_len );
if( delim ) do
{
size_t part_len;
const char * part = delim + boundary_len;
inlen -= ( part - in );
in = part;
delim = tr_memmem( in, inlen, boundary, boundary_len );
part_len = delim ? (size_t)(delim-part) : inlen;
if( part_len )
{
char * text = tr_strndup( part, part_len );
if( strstr( text, "filename=\"" ) )
{
const char * body = strstr( text, "\r\n\r\n" );
if( body )
{
char * b64, *json, *freeme;
int json_len;
size_t body_len;
tr_benc top, *args;
body += 4;
body_len = part_len - ( body - text );
if( body_len >= 2 && !memcmp(&body[body_len-2],"\r\n",2) )
body_len -= 2;
tr_bencInitDict( &top, 2 );
args = tr_bencDictAddDict( &top, "arguments", 2 );
tr_bencDictAddStr( &top, "method", "torrent-add" );
b64 = tr_base64_encode( body, body_len, NULL );
tr_bencDictAddStr( args, "metainfo", b64 );
tr_bencDictAddInt( args, "paused", paused );
json = tr_bencSaveAsJSON( &top, &json_len );
freeme = tr_rpc_request_exec_json( s->session, json, json_len, NULL );
tr_free( freeme );
tr_free( json );
tr_free( b64 );
tr_bencFree( &top );
}
}
tr_free( text );
}
}
while( delim );
evbuffer_drain( cbuf->in, EVBUFFER_LENGTH( cbuf->in ) );
tr_free( boundary );
{
/* use xml here because json responses to file uploads is trouble.
* see http://www.malsup.com/jquery/form/#sample7 for details */
const char * response = "<result>success</result>";
const int len = strlen( response );
evbuffer_add_printf( cbuf->out, "HTTP/1.1 200 OK\r\n"
"Content-Type: text/xml\r\n"
"Content-Length: %d\r\n"
"\r\n"
"%s\r\n", len, response );
}
}
if( EVBUFFER_LENGTH( cbuf->out ) )
{
const int n = MIN( ( int )EVBUFFER_LENGTH( cbuf->out ), arg->out.len );
memcpy( arg->out.buf, EVBUFFER_DATA( cbuf->out ), n );
evbuffer_drain( cbuf->out, n );
arg->out.num_bytes = n;
}
if( !EVBUFFER_LENGTH( cbuf->out ) )
{
arg->flags |= SHTTPD_END_OF_OUTPUT;
pruneBuf( s, cbuf );
}
}
static void
handle_root( struct shttpd_arg * arg )
{
const char * redirect = "HTTP/1.1 200 OK""\r\n"
"Content-Type: text/html" "\r\n"
"\r\n"
"<html><head>" "\r\n"
" <meta http-equiv=\"Refresh\" content=\"2; url=/transmission/web\">" "\r\n"
"</head><body>" "\r\n"
" <p>redirecting to <a href=\"/transmission/web\">/transmission/web</a></p>" "\r\n"
"</body></html>" "\r\n";
const size_t n = strlen( redirect );
memcpy( arg->out.buf, redirect, n );
arg->in.num_bytes = arg->in.len;
arg->out.num_bytes = n;
arg->flags |= SHTTPD_END_OF_OUTPUT;
}
static void
handle_rpc( struct shttpd_arg * arg )
{
struct tr_rpc_server * s = arg->user_data;
s->lastRequestTime = time( NULL );
struct ConnBuf * cbuf = getBuffer( s, arg );
if( !EVBUFFER_LENGTH( cbuf->out ) )
{
int len = 0;
char * response = NULL;
const char * request_method = shttpd_get_env( arg, "REQUEST_METHOD" );
const char * query_string = shttpd_get_env( arg, "QUERY_STRING" );
if( query_string && *query_string )
response = tr_rpc_request_exec_uri( s->session,
query_string,
strlen( query_string ),
&len );
else if( !strcmp( request_method, "POST" ) )
{
evbuffer_add( cbuf->in, arg->in.buf, arg->in.len );
arg->in.num_bytes = arg->in.len;
if( arg->flags & SHTTPD_MORE_POST_DATA )
return;
response = tr_rpc_request_exec_json( s->session,
EVBUFFER_DATA( cbuf->in ),
EVBUFFER_LENGTH( cbuf->in ),
&len );
evbuffer_drain( cbuf->in, EVBUFFER_LENGTH( cbuf->in ) );
}
evbuffer_add_printf( cbuf->out, "HTTP/1.1 200 OK\r\n"
"Content-Type: application/json\r\n"
"Content-Length: %d\r\n"
"\r\n"
"%*.*s", len, len, len, response );
tr_free( response );
}
if( EVBUFFER_LENGTH( cbuf->out ) )
{
const int n = MIN( ( int )EVBUFFER_LENGTH( cbuf->out ), arg->out.len );
memcpy( arg->out.buf, EVBUFFER_DATA( cbuf->out ), n );
evbuffer_drain( cbuf->out, n );
arg->out.num_bytes = n;
}
if( !EVBUFFER_LENGTH( cbuf->out ) )
{
arg->flags |= SHTTPD_END_OF_OUTPUT;
pruneBuf( s, cbuf );
}
}
static void
rpcPulse( int socket UNUSED, short action UNUSED, void * vserver )
{
int interval;
struct timeval tv;
tr_rpc_server * server = vserver;
const time_t now = time( NULL );
assert( server );
if( server->ctx )
shttpd_poll( server->ctx, 1 );
/* set a timer for the next pulse */
if( now - server->lastRequestTime < 300 )
interval = ACTIVE_INTERVAL_MSEC;
else
interval = INACTIVE_INTERVAL_MSEC;
tv = tr_timevalMsec( interval );
evtimer_add( &server->timer, &tv );
}
static void
getPasswordFile( tr_rpc_server * server, char * buf, int buflen )
{
tr_buildPath( buf, buflen, tr_sessionGetConfigDir( server->session ),
"htpasswd",
NULL );
}
static void
startServer( tr_rpc_server * server )
{
dbgmsg( "in startServer; current context is %p", server->ctx );
if( !server->ctx )
{
int i;
int argc = 0;
char * argv[100];
char passwd[MAX_PATH_LENGTH];
const char * clutchDir = tr_getClutchDir( server->session );
struct timeval tv = tr_timevalMsec( INACTIVE_INTERVAL_MSEC );
getPasswordFile( server, passwd, sizeof( passwd ) );
if( !server->isPasswordEnabled )
unlink( passwd );
else
edit_passwords( passwd, MY_REALM, server->username, server->password );
argv[argc++] = tr_strdup( "appname-unused" );
argv[argc++] = tr_strdup( "-ports" );
argv[argc++] = tr_strdup_printf( "%d", server->port );
argv[argc++] = tr_strdup( "-dir_list" );
argv[argc++] = tr_strdup( "0" );
argv[argc++] = tr_strdup( "-auth_realm" );
argv[argc++] = tr_strdup( MY_REALM );
if( server->acl )
{
argv[argc++] = tr_strdup( "-acl" );
argv[argc++] = tr_strdup( server->acl );
}
if( server->isPasswordEnabled )
{
argv[argc++] = tr_strdup( "-protect" );
argv[argc++] = tr_strdup_printf( "/transmission=%s", passwd );
}
if( clutchDir && *clutchDir )
{
tr_inf( _( "Serving the web interface files from \"%s\"" ), clutchDir );
argv[argc++] = tr_strdup( "-aliases" );
argv[argc++] = tr_strdup_printf( "%s=%s,%s=%s",
"/transmission/clutch", clutchDir,
"/transmission/web", clutchDir );
}
argv[argc] = NULL; /* shttpd_init() wants it null-terminated */
server->ctx = shttpd_init( argc, argv );
shttpd_register_uri( server->ctx, "/transmission/rpc", handle_rpc, server );
shttpd_register_uri( server->ctx, "/transmission/upload", handle_upload, server );
shttpd_register_uri( server->ctx, "/", handle_root, server );
evtimer_set( &server->timer, rpcPulse, server );
evtimer_add( &server->timer, &tv );
for( i=0; i<argc; ++i )
tr_free( argv[i] );
}
}
static void
stopServer( tr_rpc_server * server )
{
if( server->ctx )
{
char passwd[MAX_PATH_LENGTH];
getPasswordFile( server, passwd, sizeof( passwd ) );
unlink( passwd );
evtimer_del( &server->timer );
shttpd_fini( server->ctx );
server->ctx = NULL;
}
}
void
tr_rpcSetEnabled( tr_rpc_server * server, int isEnabled )
{
if( !isEnabled && server->ctx )
stopServer( server );
if( isEnabled && !server->ctx )
startServer( server );
}
int
tr_rpcIsEnabled( const tr_rpc_server * server )
{
return server->ctx != NULL;
}
void
tr_rpcSetPort( tr_rpc_server * server, int port )
{
if( server->port != port )
{
server->port = port;
if( server->ctx )
{
stopServer( server );
startServer( server );
}
}
}
int
tr_rpcGetPort( const tr_rpc_server * server )
{
return server->port;
}
/****
***** ACL
****/
/*
* FOR_EACH_WORD_IN_LIST, isbyte, and testACL are from, or modified from,
* shttpd, written by Sergey Lyubka under this license:
* "THE BEER-WARE LICENSE" (Revision 42):
* Sergey Lyubka wrote this file. As long as you retain this notice you
* can do whatever you want with this stuff. If we meet some day, and you think
* this stuff is worth it, you can buy me a beer in return.
*/
#define FOR_EACH_WORD_IN_LIST(s,len) \
for (; s != NULL && (len = strcspn(s, DELIM_CHARS)) != 0; \
s += len, s+= strspn(s, DELIM_CHARS))
static int isbyte(int n) { return (n >= 0 && n <= 255); }
static char*
testACL( const char * s )
{
int len;
FOR_EACH_WORD_IN_LIST(s, len)
{
char flag;
int a, b, c, d, n, mask;
if( sscanf(s, "%c%d.%d.%d.%d%n",&flag,&a,&b,&c,&d,&n) != 5 )
return tr_strdup_printf( _( "[%s]: subnet must be [+|-]x.x.x.x[/x]" ), s );
if( flag != '+' && flag != '-')
return tr_strdup_printf( _( "[%s]: flag must be + or -" ), s );
if( !isbyte(a) || !isbyte(b) || !isbyte(c) || !isbyte(d) )
return tr_strdup_printf( _( "[%s]: bad ip address" ), s );
if( sscanf(s + n, "/%d", &mask) == 1 && ( mask<0 || mask>32 ) )
return tr_strdup_printf( _( "[%s]: bad subnet mask %d" ), s, n );
}
return NULL;
}
/* 192.*.*.* --> 192.0.0.0/8
192.64.*.* --> 192.64.0.0/16
192.64.1.* --> 192.64.1.0/24
192.64.1.2 --> 192.64.1.2/32 */
static void
cidrizeOne( const char * in, int len, struct evbuffer * out )
{
int stars = 0;
const char * pch;
const char * end;
char zero = '0';
char huh = '?';
for( pch=in, end=pch+len; pch!=end; ++pch ) {
if( stars && isdigit(*pch) )
evbuffer_add( out, &huh, 1 );
else if( *pch!='*' )
evbuffer_add( out, pch, 1 );
else {
evbuffer_add( out, &zero, 1 );
++stars;
}
}
evbuffer_add_printf( out, "/%d", (32-(stars*8)));
}
char*
cidrize( const char * acl )
{
int len;
const char * walk = acl;
char * ret;
struct evbuffer * out = evbuffer_new( );
FOR_EACH_WORD_IN_LIST( walk, len )
{
cidrizeOne( walk, len, out );
evbuffer_add_printf( out, "," );
}
/* the -1 is to eat the final ", " */
ret = tr_strndup( (char*) EVBUFFER_DATA(out), EVBUFFER_LENGTH(out)-1 );
evbuffer_free( out );
return ret;
}
int
tr_rpcTestACL( const tr_rpc_server * server UNUSED,
const char * acl,
char ** setme_errmsg )
{
int err = 0;
char * cidr = cidrize( acl );
char * errmsg = testACL( cidr );
if( errmsg )
{
if( setme_errmsg )
*setme_errmsg = errmsg;
else
tr_free( errmsg );
err = -1;
}
tr_free( cidr );
return err;
}
int
tr_rpcSetACL( tr_rpc_server * server,
const char * acl,
char ** setme_errmsg )
{
char * cidr = cidrize( acl );
const int err = tr_rpcTestACL( server, cidr, setme_errmsg );
if( !err )
{
const int isRunning = server->ctx != NULL;
if( isRunning )
stopServer( server );
tr_free( server->acl );
server->acl = tr_strdup( cidr );
dbgmsg( "setting our ACL to [%s]", server->acl );
if( isRunning )
startServer( server );
}
tr_free( cidr );
return err;
}
char*
tr_rpcGetACL( const tr_rpc_server * server )
{
return tr_strdup( server->acl ? server->acl : "" );
}
/****
***** PASSWORD
****/
void
tr_rpcSetUsername( tr_rpc_server * server,
const char * username )
{
const int isRunning = server->ctx != NULL;
if( isRunning )
stopServer( server );
tr_free( server->username );
server->username = tr_strdup( username );
dbgmsg( "setting our Username to [%s]", server->username );
if( isRunning )
startServer( server );
}
char*
tr_rpcGetUsername( const tr_rpc_server * server )
{
return tr_strdup( server->username ? server->username : "" );
}
void
tr_rpcSetPassword( tr_rpc_server * server,
const char * password )
{
const int isRunning = server->ctx != NULL;
if( isRunning )
stopServer( server );
tr_free( server->password );
server->password = tr_strdup( password );
dbgmsg( "setting our Password to [%s]", server->password );
if( isRunning )
startServer( server );
}
char*
tr_rpcGetPassword( const tr_rpc_server * server )
{
return tr_strdup( server->password ? server->password : "" );
}
void
tr_rpcSetPasswordEnabled( tr_rpc_server * server,
int isEnabled )
{
const int isRunning = server->ctx != NULL;
if( isRunning )
stopServer( server );
server->isPasswordEnabled = isEnabled;
dbgmsg( "setting 'password enabled' to %d", isEnabled );
if( isRunning )
startServer( server );
}
int
tr_rpcIsPasswordEnabled( const tr_rpc_server * server )
{
return server->isPasswordEnabled;
}
/****
***** LIFE CYCLE
****/
void
tr_rpcClose( tr_rpc_server ** ps )
{
tr_rpc_server * s = *ps;
*ps = NULL;
stopServer( s );
tr_free( s->username );
tr_free( s->password );
tr_free( s->acl );
tr_free( s );
}
tr_rpc_server *
tr_rpcInit( tr_handle * session,
int isEnabled,
int port,
const char * acl,
int isPasswordEnabled,
const char * username,
const char * password )
{
char * errmsg;
tr_rpc_server * s;
if(( errmsg = testACL ( acl )))
{
tr_nerr( MY_NAME, errmsg );
tr_free( errmsg );
acl = TR_DEFAULT_RPC_ACL;
tr_nerr( MY_NAME, "using fallback ACL \"%s\"", acl );
}
s = tr_new0( tr_rpc_server, 1 );
s->session = session;
s->port = port;
s->acl = tr_strdup( acl );
s->username = tr_strdup( username );
s->password = tr_strdup( password );
s->isPasswordEnabled = isPasswordEnabled;
if( isEnabled )
startServer( s );
return s;
}